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991.
We screened all head-injured trauma patients admitted to Lehigh Valley Hospital during a 2-year period. From 725 screened patients, 69 patients in a coma on the second day after trauma were entered into this study. During the first week, these patients underwent electroencephalography (EEG), evoked potentials, ocular pneumoplethysmography, and transcranial Doppler (TCD) sonography. Clinical examinations were undertaken 2 and 7 days after trauma. Test results were correlated with functional clinical outcome at 6 months. In a multiple regression analysis, EEG was the major independent variable that significantly predicted 6-month outcome based on Glasgow Outcome Scale score. Transcranial Doppler sonography contributed a small additional component. Though EEG was the most significant predictive factor in this neurophysiological battery, it did not add significantly to the predictive power of Glasgow Coma Scale score determined at day 7. These findings suggest that in neurophysiologic testing in this type of patient is not useful in improving predictive outcome data.  相似文献   
992.
993.
The purpose of this study was to examine the effects of excessive fluid in the knee joint on proprioception. Twenty healthy subjects with no knee pathology participated in this study. Subjects were randomly assigned to control and experimental groups. Baseline measurements of subjects performing a tracking task were then recorded. Specifically, one knee joint was moved passively by a dynamometer through a range of motion from approximately 90 degrees flexion to 10 degrees from full extension at a joint angular velocity of 60 degrees/sec. Subjects were blindfolded and required to track the passively moving joint as accurately as possible for a period of 1.25 minutes with the opposite limb. An electrogoniometer was used to monitor the motion of the active tracking limb. Ninety mL of a solution of saline and dextrose were injected into the knee joint cavity of the experimental subjects, and they repeated the tracking task. After a 5-minute rest, the control group subjects also repeated the task. The results indicated that the injection of fluid did not change the subjects' error in tracking the passively moving limb (p > 0.05). No change in the error associated with tracking was observed for the control group (p > 0.05). It is suggested that the effects of long-term effusions and the nature of the inflammatory fluid might be more responsible for the loss of proprioception observed in some clinical conditions.  相似文献   
994.
Forty-five patients with schizophrenia or schizophreniform disorder admitted to hospital for the first time had a neurological examination, including integrative sensory and complex motor acts, by a trained neurologist. The patients were studied by CT and regional cerebral blood flow as well. A control group of 24 healthy volunteers was included. The patients had significantly more neurological abnormalities (NA) than the healthy volunteers. Medication did not explain the discrepancy. The NA were associated with sulcal enlargement and smaller brains as visualized by CT but not with ventricular enlargement. There was no association between the regional flow values and NA.  相似文献   
995.
996.
Quinolinic acid (QUIN) is a tryptophan metabolite which has been found to be an excitotoxin in rats, although its toxicity in humans is unknown. QUIN has been implicated in the pathogenesis of AIDS dementia complex. This study examined the effect of QUIN on human fetal brain tissue in vitro. After at least 14 days in vitro, QUIN was added to the cultures in the feeding medium, and lactate dehydrogenase (LDH) efflux at 20 h and neuronal morphology were used as a measure of neuronal injury. LDH levels in media from cultures exposed to QUIN concentrations of 5 and 10 mM were consistently elevated compared to controls. Overall, LDH levels in media from cultures exposed to lower QUIN concentrations did not differ significantly from controls. These data are comparable to animal in vitro studies, and support the hypothesis that QUIN is toxic to human central nervous system neurons and further strengthen its potential role in the pathogenesis of AIDS dementia complex.  相似文献   
997.
We re-examined clinically and radiologically 88 patients with a fracture of the lower leg at a mean follow-up of 15 years. Forty-three fractures (49%) had healed with malalignment of at least 5 degrees. More arthritis was found in the knee and ankle adjacent to the fracture than in the comparable joints of the uninjured leg. Malaligned fractures showed significantly more degenerative changes. Eighteen patients (20%) had symptoms in the fractured leg. There was a significant correlation between symptoms in the knee and arthritis but not between symptoms and ankle arthritis or malalignment. We conclude that fractures of the lower leg should be managed so that the possibility of angular deformity and thereby late arthritis is minimised.  相似文献   
998.
The presence of various sterols in mixtures with dihexadecylphosphatidylcholine (DHPC) was studied using static X-ray diffraction of temperature equilibrated samples, and real-time X-ray diffraction of samples undergoing temperature scans. It was found that these sterols eliminate the interdigitation of the alkyl chains in the DHPC sub-gel and gel-state bilayers while stabilizing the ripple gel-state at the expense of the gel-state bilayer phase. The ripple-ripple phase transition previously observed for dipalmitoylphosphatidylcholine in the presence of low molar concentrations of sterols (Wolfe et al. (1992) Phys. Rev. Lett. 68, 1085-1088) was also observed for similar DHPC-sterol mixtures. In addition, we show the first evidence that the presence of 5 alpha-cholestane-3 beta,5,6 beta-triol will cause the lipid mixtures to continue to adopt a ripple mesophase structure even after the DHPC alkyl chain becomes disordered.  相似文献   
999.
Projects are being carried out in many regions of Egypt to reclaim land from the desert for agriculture. This paper presents findings from a baseline epidemiologic study conducted in 1992 in two newly reclaimed areas near Ismailia, Egypt. In the first area, just east of the Suez Canal, 40.0% of the residents tested positive for Schistosoma mansoni and 1.7% tested positive for S. haematobium, while in the second area, 15 km southwest of Ismailia, 49.3% tested positive for S. mansoni and 3.3% tested positive for S. haematobium. The intensities of S. mansoni infection were moderately high, with a geometric mean egg count of 76 eggs/gram of feces among positive individuals in the first area, and 100 eggs/gram of feces in the second area. When compared with a previous study conducted in 1985, the prevalence of S. mansoni infection in the first area has increased from 21.7% to 42.1% among settlers in the last seven years, while that of S. haematobium has decreased from 7.8% to 1.7%. These trends may result from changes in irrigation practices or other alterations in the local environment. There is a risk of schistosomiasis becoming a major public health problem in reclaimed areas if adequate control measures are not taken.  相似文献   
1000.
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